Improvement in trying-squares



T. W. WISNER.

Try Square. 7 No. 36.977. Patented Nov. 18, 1862.

N. FETERS Fhnln-Llkhogmpher, Washington, D.C,

UNITED STATES PATENT OFFICE.

T. W. WISNER, OF OSOEOLA, MICHIGAN.

IMPROVEMENT IN TRYING-SQUARES.

Specification forming part of Letters Patent No. 36,91 7, dated November18, 1362.

To aZZ whom it may concern:

Be it known that I, T. W. VVIsNER, of Osceola, in the county ofLivingston and State of Michigan, have invented a new and ImprovedTrying-Square; and I do hereby declare that the following is afull,clear, and exact description of the same, reference being had to theaccompanying drawings, making a part of this specification, in which-Figure 1 is a side view of my invention; Fig. 2, a section of the same,taken in the line a: as, Fig. 1.

Similar letters of reference indicate correspondin g parts in the twofigures.

This invention relates to a new and useful improvement intrying-squares, such as are used by joiners and other workers in woodfor testing surfaces which are designed to be at right angles with eachother.

The object of the invention is to' obtain a simple means for keeping thesquare perfectly true, so that the blade of the square will always be atright angles with the face-plate of the stock.

To this end the invention consists in having the face-plate of the stockarranged in such a manner that it may be adjusted to compensate for anyvariation that might. occur between the blade and stock.

To enable those skilled in the art to fully understand my invention, Iwill proceed to de scribe it. I

A represents the blade of the square, which is constructed, as usual, ofsteel-plate, and B is the stock, constructed of wood, the blade andstock being connected together at right angles by rivets to. These partsare arranged in the ordinary way, and therefore do not require a minutedescription.

0 represents a metal faceplate, which is screw, which passes through thestock B and into the lower part of the face-plate C, the latter having ahole in it provided with an internal screw to receive the end of thescrew 1), as shown clearly in Fig. 1. The screw D has a shoulder orcollar, 6, upon it, which bears against the inner side of a metal plate,f, attached to the lower part of the stock, as shown clearly in Fig. 1.By turning the screw D, it will be seen that the face-plate C may beadjusted in or out from the stock B, the former working on the pin (7.This will be fully understood by referring to Fig. in which theface-plate is shown in tint as being adjusted snugly to the stock, andshown adjusted out from it in red outline.

From the above description, therefore, it will be seen that in case theplate A and the stock B get out of a proper relative position with eachother, (a right angular one,) they may be readily adjusted in properposition by turning the sc ew 1) so as to bring the outer surface of theface-place (J at right angles with the blade A. Tryingsquares, even ifmade true or correct, are very liable to get incorrect or untrue fromthe shrinking and warping of the handle and other causes. Thisdifficulty is fully obviated by my invention. It will be seen that thestock B is never changed in position, for it always remains permanentlyattached to the blade A. The shifting of the face-plate O is all theadjustment thatis necessary in order to render the'square perfectlytrue. It the stock B were made adjustable it would be liable to slip ormove casually and render the implement very unreliable.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

The adjustable face-plate (J, applied to the stock B ofthe square,substantially as shown, and operated bythe screw D, or its equivalent,for the purpose specified.

T. W. WISNER.

Witnesses:

MYLO L. GAY, GEO. L. SAYE.

